Variables con posible capacidad modificadora del PSA ajustado al volumen de la zona transicional

Abstract

ObjectiveTo evaluate the effect of age, digital rectal examination results and prostatic volume on PSA value adjusted to transition zone (PSA-TZ) in the detection of prostatic cancer. Material and methodsData of 243 patients with serum PSA of 4 to 20 ng/ml who underwent biopsy because of prostatic cancer suspicion are analyzed. In this population, cancer was detected in 62 cases (24.8%). Total prostatic volume and transition zone volume were calculated by transrectal echography applying the ellipsoid formula. ResultsApplying lineal regresion analysis, it was found no correlation between age and PSA-TZ (Pearson coefficient 0,00). By dividing these patients among those with normal rectal examination (84%) and those with suspicious digital rectal examination (16%), cutoff values of PSA-TZ were found to be not different by ROC curves analysis for 95% sensitivity varying specificity only among 24 and 26% between these two groups of patients. Prostatic size (≤ or > 40 cc) showed that, for obtaining the same 95% sensitivity in the detection of cancer, PSA-TZ value would require to be modified, being 0.17 in large prostates (> 40 cc) and 0.25 in small prostates (≤ 40 cc). ConclusionsThe utility of PSA-TZ as a potential predictor parameter of prostatic cancer did not need to be modified with respect to age or to data of digital rectal examination. However, for supporting sensivity of its best cutoff value, PSA-TZ would need to be modified with respect to total prostatic volume.